This is a more general infra problem rather than a specific issue, so this BZ is just an example of a more general problem,
This is a long invocation and involves creation of async tasks,
The problem is that async tasks 'loose' the context of the user,
In the infra level there should be a support for preserving user context.

It looks like the user in the event is taken at the end of the command execution, hence the session does not exist and user = UNKNOWN
Eli suggested to add the user to the command base.
In this case this should be an easy fix.